1. Field of the Invention
The present invention relates to computer input devices and, more particularly, to keyboards for providing input to computing devices.
2. Related Art
Most computing devices use a keyboard or keypad for providing alphanumeric and other input to the computing device. For example, most conventional desktop and laptop computers employ a keyboard including both alphanumeric keys for providing alphanumeric input to the computer and a variety of function keys for issuing commands to the computer. The layout of the alphanumeric keys on such keyboards is typically based on the standard employed by conventional manual typewriters. In particular, the alphabetic keys are arranged in what is commonly referred to as a QWERTY layout because the upper row of alphabetic keys begins with the letters Q, W, E, R, T, and Y.
One advantage of using the QWERTY layout to arrange keys on a computer keyboard is that large numbers of users are already familiar with the QWERTY layout. Typists have been trained for many years to touch-type using keyboards having the QWERTY layout (referred to herein simply as “QWERTY keyboards”), resulting in a large base of users who are skilled at typing relatively quickly and accurately using QWERTY keyboards. Organizations and individuals have invested significant resources in developing the skills necessary to type proficiently using QWERTY keyboards. As a result, a new computing device having a QWERTY keyboard is likely to meet with more acceptance and to require less training than a computing device with a keyboard having a different layout.
There are, however, problems with the QWERTY layout. It can be difficult for novice typists to learn how to type using QWERTY keyboards, at least in part because the keys in the QWERTY layout are not arranged alphabetically. Although it is possible to learn to touch-type relatively quickly and accurately using a QWERTY keyboard, doing so can take a significant amount of training and require significant ongoing practice in order to maintain high levels of speed and accuracy.
Furthermore, some frequently-used keys are so located in the QWERTY layout as to require movement of the fingers to reach them, while some less-frequently used keys are so located as to be easily reached. As a result, typing using a QWERTY keyboard may result in typing speeds and error rates that are less than optimal.
Conventional computer keyboards compound these problems by introducing large numbers of additional keys, such as function keys, numeric data entry keys, and cursor positioning keys. The total number of keys on a conventional computer keyboard typically exceeds one hundred. The difficulty of remembering the precise location of each key on such a keyboard, in combination with the amount of finger movement required to type on such a keyboard, can further reduce typing speed and accuracy. When using such keyboards, even trained touch typists may mistype individual keys on occasion, particularly when typing keys that are dispersed throughout the keyboard. Users who type using the “hunt and peck” method may also mistype keys for a variety of reasons, such as poor hand-eye coordination or out of an attempt to type too quickly.
Various attempts have been made to devise improved keyboards to increase typing speeds and/or decrease typing error rates. For example, some keyboards use layouts other than the QWERTY layout. Some of these alternative layouts are designed to place the most frequently-used keys directly underneath the user's fingers so that it is not necessary to move the fingers in order to reach such keys. Some layouts place the most-frequently used keys directly underneath or near the user's strongest fingers, such as the index and pointer fingers, and the less-frequently used keys directly underneath or near the user's weakest fingers, such as the ring finger.
Other alternative keyboards assign multiple characters to individual keys on the keyboard, thereby reducing the total number of keys on the keyboard and correspondingly reducing the number of fingers that are required to type and/or the amount of finger motion used while typing. The goal of such alternative keyboard layouts is to increase typing speed and/or reduce typing error rates. With some keyboards, a particular character is input by pressing a particular key in a particular way (such as by pressing the key at one corner to input one character and at another corner to input a different character), or by repeatedly pressing a particular key a different number of times in order to specify different characters. Some schemes employ algorithms to predict which character the user desires to input based on various factors.
All of the alternative layouts described above have the disadvantage that they do not retain the QWERTY layout to which so many users have become accustomed. Any potential increase in speed or reduction in error rate that may be attained as a result of such alternative layouts must be weighed against the costs associated with retraining users who have become accustomed to and adept at using the QWERTY layout. In fact, none of the alternative keyboard layouts described above has met with significant success, at least in part as a result of the extremely deep penetration of the QWERTY layout and its widespread acceptance.
What is needed, therefore, is an improved keyboard that increases typing speed and/or reduces typing error rates, and that is compatible with the QWERTY keyboard layout.